PhoneticAlphabetConverter.java

package com.thealgorithms.conversions;

import java.util.HashMap;
import java.util.Map;

/**
 * Converts text to the NATO phonetic alphabet.
 * Examples:
 * "ABC" -> "Alpha Bravo Charlie"
 * "Hello" -> "Hotel Echo Lima Lima Oscar"
 * "123" -> "One Two Three"
 * "A1B2C3" -> "Alpha One Bravo Two Charlie Three"
 *
 * @author Hardvan
 */
public final class PhoneticAlphabetConverter {
    private PhoneticAlphabetConverter() {
    }

    private static final Map<Character, String> PHONETIC_MAP = new HashMap<>();

    static {
        PHONETIC_MAP.put('A', "Alpha");
        PHONETIC_MAP.put('B', "Bravo");
        PHONETIC_MAP.put('C', "Charlie");
        PHONETIC_MAP.put('D', "Delta");
        PHONETIC_MAP.put('E', "Echo");
        PHONETIC_MAP.put('F', "Foxtrot");
        PHONETIC_MAP.put('G', "Golf");
        PHONETIC_MAP.put('H', "Hotel");
        PHONETIC_MAP.put('I', "India");
        PHONETIC_MAP.put('J', "Juliett");
        PHONETIC_MAP.put('K', "Kilo");
        PHONETIC_MAP.put('L', "Lima");
        PHONETIC_MAP.put('M', "Mike");
        PHONETIC_MAP.put('N', "November");
        PHONETIC_MAP.put('O', "Oscar");
        PHONETIC_MAP.put('P', "Papa");
        PHONETIC_MAP.put('Q', "Quebec");
        PHONETIC_MAP.put('R', "Romeo");
        PHONETIC_MAP.put('S', "Sierra");
        PHONETIC_MAP.put('T', "Tango");
        PHONETIC_MAP.put('U', "Uniform");
        PHONETIC_MAP.put('V', "Victor");
        PHONETIC_MAP.put('W', "Whiskey");
        PHONETIC_MAP.put('X', "X-ray");
        PHONETIC_MAP.put('Y', "Yankee");
        PHONETIC_MAP.put('Z', "Zulu");
        PHONETIC_MAP.put('0', "Zero");
        PHONETIC_MAP.put('1', "One");
        PHONETIC_MAP.put('2', "Two");
        PHONETIC_MAP.put('3', "Three");
        PHONETIC_MAP.put('4', "Four");
        PHONETIC_MAP.put('5', "Five");
        PHONETIC_MAP.put('6', "Six");
        PHONETIC_MAP.put('7', "Seven");
        PHONETIC_MAP.put('8', "Eight");
        PHONETIC_MAP.put('9', "Nine");
    }

    /**
     * Converts text to the NATO phonetic alphabet.
     * Steps:
     * 1. Convert the text to uppercase.
     * 2. Iterate over each character in the text.
     * 3. Get the phonetic equivalent of the character from the map.
     * 4. Append the phonetic equivalent to the result.
     * 5. Append a space to separate the phonetic equivalents.
     * 6. Return the result.
     *
     * @param text the text to convert
     * @return the NATO phonetic alphabet
     */
    public static String textToPhonetic(String text) {
        StringBuilder phonetic = new StringBuilder();
        for (char c : text.toUpperCase().toCharArray()) {
            if (Character.isWhitespace(c)) {
                continue;
            }
            phonetic.append(PHONETIC_MAP.getOrDefault(c, String.valueOf(c))).append(" ");
        }
        return phonetic.toString().trim();
    }
}